Heat treating furnace



W. E. BLYTHE June 12, 1934.

HEAT ,TREAT ING FURNACE Original Filed Feb. 21, 1930 Q w v a my INVENTORKilian EB MM TTORNEYS Reissued June 12, 1934 HEAT TREATING FURNACEWilliam E. Blythe, Birmingham, Mich, assignor to Driver-Harris Company,Harrison, N. J., a corporation of New Jersey -'Original No. 1,843,440,dated February 2, 1932,

Serial No. 430,193, February 21, 1930. Applicagianwfor reissue January23, 1934, Serial No.

6 Claims. (Cl. 263-6) My invention relates to high temperatureheatireating furnaces of the type in which the material to be treated isconveyed through the furnace on rolls, each roll usually consisting of ashaft carrying wheels or disks ,with the .disks of the several rollsarranged in staggered relation.

One of the objects of my invention is to provide a furnace of thecharacter indicated in which the conveyor rolls are capable ofwithstanding the intense heat of the furnace without resorting to theuse of water or other cooling agent, and in which the shafts of therolls may be made of small diameter so as to permit the rolls to bepositioned with their axes in close proximity.

Another object of the invention is to provide a novel and improvedconveyor roll for a high temperature heat-treating furnace of thecharacter indicated.

The several features of the invention whereby 2o attained, will bereadily understood from the following description andflaccompanyingdrawing, in which: I a

Figure 1 is a transversesectional view, partly in elevation, of aportion'of a furnace embodying the features of my invention in theirpreferred form; j

. Fig. 2 is a detail sectional plan'view taken substantially on the line2-2 of Fig. 1';

Fig. 3 is a detail end view of the shaft of one of the rolls and itssupporting bearing. 7

The furnace illustrated in the drawing is provided with a furnacechamber having side walls 2, a top wall 4, and a bottom wall 6,.andconveyor rolls extending transversely of the furnacechamber, each rollcomprising a shaft 8 and material conveying disks 10 secured thereon.The disks 10 of the several rolls are arranged in' staggered relation soas to permit each diskto extend into the spaces between adjacent disksof adjacent rolls with the periphery of the disk positioned in closeproximity to the shafts of the adjacent rolls.

In accordance with my invention, the ends of the shafts are supported onroller bearings 12 that are mounted in cradles 14 set into or secured inrecesses 16 in the inner sides of the side walls of the furnace chamber,the ends of each shaft extending only a slight distance beyond the outersides of the roller bearings. One side wall of the furnace chamber isclosed. The other side wall is provided with cylindrical openings 18 insubstantial alinement with the roll shafts 8. Eachconveyor roll isdriven by a drive shaft 20 that 55 may be mounted in a suitable bearingon a supthe above-mentioned and other objects may be porting bracket 22on the outside of the furnace. Each shaft 20 is arranged in axialalinement with the shaft of the associated conveyor roll and isconnected with the roll shaft by a. suitable fiexible coupling 24. Asshown, this coupling consists c0 of a collar or sleeve which istelescoped over the adjacent ends of the. associated drive shaft androll shaft and is loosely connected therewith by bolts 26 arrangedtransversely of each other, and extended through apertures in thecoupling sleeve and the ends of the shafts. The conveyor roll shafts maybe made hollow, and said shafts, couplings, conveyor disks and rollerbearings may be made of a suitable heat-resisting alloy.

With this construction, it will be apparent that the shafts of theconveyor rolls are of minimum length and thus are capable of much moreeffectively withstanding the intense heat of the furnace and the weightof the material without sagging at their centers than is the case withrolls in which walls and are supported in bearings outside of thefurnace chamber as heretofore has been customary. Heretofore, it hasbeen attempted to increase the strength of the shafts of conveyor rollsby increasing their diameters, but this has not proven satisfactory forthe reason that it is necessary for the shafts to ,be of as smalldiameter as possible in order to permit them to be positioned with theiraxes close together so as to allow the disks of the rolls to engage thematerial at closely spaced points. Y

' The conveyor rolls are mounted insuch a manner as to allow forexpansion and contraction, and close fitting of parts is unnecessary.

Owing to the small size and weight of my improved conveyor rolls theyare relatively cheap to manufacture, and require less power to operate.

As will be evident to those skilled in the art, my invention permitsvarious modifications without departing from the spirit thereof or thescope of the appended claims.

What I claim is:

1. In a heat-treating furnace of the class described, the combination ofa furnace chamber having side walls, conveyor rolls extending betweenthe side walls, bearings for the ends of said rolls mounted adjacent theinner sides of the side walls, one of the side walls having an openingin alinement with each roll, and means for driving said roll comprisinga drive shaft, 9. bearing for the drive shaft arranged outside of thefurnace, and couplingmeans connecting one end of each roll with itsdrive shaft through the opening associated with the roll, said conveyorno 75 their shafts extend through apertures in the side tirely withinthe furnace chamber. 7

2. In a heat-treating furnace of the class described, the combination ofa furnace chamber having side walls, a conveyor roll extending be tweenthe side walls, bearings for the ends of said roll set into said sidewalls one of said side walls having an opening in alinement with'saidroll, a drive shaft for the roll, and a flexible vcoupling connectingone end of the drive shaft with one end of the roll, said end of thedrive shaft extending into said opening, and the ends of said roll beingspaced inwardly from the outer sides of said side walls, said conveyorrolls and the bearings therefor being located entirely within thefurnace chamber. 1

3. In a heat-treating furnace ofthe class described, the combination ofa furnace chamber having side walls, conveyor rolls extending betweenand located whollywithin the side walls, each roll comprising a hollowshaft and disks secured,on the shaft in spaced relation with the disksof the several rolls arranged in staggered relation with the peripheryof each dish arranged in close proximity to the peripheral S111? facesof adjacent shafts, the inner sides of each of the side walls being Prvided with recesses, roller bearings mounted in said recesses forsupporting the ends of the shafts, one of said side walls being closed,and the other side wall having openings in substantial alinement withthe rolls extending into the opening in alinement. with the roll, andflexible coupling means connecting the inner ends of said drive shaftand shafts of the rolls, a drive shaftfor each of the the adjacent endsof the shafts of thewrolls.

4. Ina heat-treating furnace of the class derolls and the bearingstherefor being located enscribed, the combination of a furnace chamber,conveyor rolls extending across the furnace chamber, means forsupporting the rolls for rotary movement comprising bearing rollers onwhich the 'conveyor rolls rest, supports for the bearing rolls,'saidconveyor rolls, bearing rollers and supports for the bearing rollersbeing located entirely within the furnace chamber, and means independentof the bearing rollers for rotating the several conveyor rolls, thebearing rollers being freely rotatable by engagement with the rotatingconveyor rolls.

5. In a heat-treating furnace, a furnace chamber having side walls,conveyor rolls extending across the furnace chamber with at least oneend of each roll spaced a distance inwardly from the outer side of theadjacent side wall, bearingsfor each of the rolls spaced a distanceinwardly from the outer sides of the side walls, driving means for eachof the conveyor rolls located outside of the furnace chamber; and meansfor flexibly coupling each of the rolls'to its driving means.

6. In a heat-treating furnace of the class described, a furnace chamberhaving side walls, conveyor rolls extending across the furnace chamberwith at least one end of each of the rolls spaced a distance inwardlyfrom the outer side of the adjacent side wall, bearings for supportingeach of the rolls spaced inwardly from the outer sides of said sidewalls, each bearing comprising bearing rollers upon which the conveyorroll rests, a driving shaft for each of the rolls, means located outsideof the furnace chamber for supporting said driving shaft, and flexiblecoupling means connecting said driving shaft with its conveyor roll.

Ill

